This patch enables TCP checksum offload support for IPv6 on ibmveth.
This completely eliminates the generation and checking of the checksum
for IPv6 packets that are completely virtual and never touch a physical
network.  A basic TCPIPV6_STREAM netperf run showed a ~30% throughput
improvement when an MTU of 64000 was used.

This featured is enabled by default, as is the case for IPv4 checksum
offload.  When checksum offload is enabled the driver will negotiate
IPv4 and IPv6 offload with the firmware separately and enable what
is available.  As long as either IPv4 or IPv6 offload is supported
and enabled the device will report that checksum offload is enabled.
The device stats, available through ethtool, will display which
checksum offload features are supported/enabled by firmware.

Performance testing against a stock kernel shows no regression for IPv4
or IPv6 in terms of throughput or processor utilization with checksum
disabled or enabled.
Signed-off-by: NRobert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove code in the device probe function where we set up the checksum
offload feature and replace it with a call to an existing function that
is doing the same.  This is done to clean up the driver in preparation
of adding IPv6 checksum offload support.
Signed-off-by: NRobert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On some machines we can improve the bandwidth by ensuring rx buffers are
not in the cache. Add a module option that is disabled by default that flushes
rx buffers on insertion.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ibmveth can scatter gather up to 6 segments. If we go over this then
we have no option but to call skb_linearize, like other drivers with
similar limitations do.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We want to order the read in ibmveth_rxq_pending_buffer and the read of
ibmveth_rxq_buffer_valid which are both cacheable memory. smp_rmb() is good
enough for this.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For small packets, create a new skb and copy the packet into it so we
avoid tearing down and creating a TCE entry.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the existing bounce buffer if we send a buffer under a certain size.
This saves the overhead of a TCE map/unmap.

I can't see any reason for the wmb() in the bounce buffer case, if we need
a barrier it will be before we call h_send_logical_lan but we have
nothing in the common case. Remove it.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ibmveth adapter needs locking in the transmit routine to protect
the bounce_buffer but it sets LLTX and forgets to add any of its own
locking.

Just remove the deprecated LLTX option. Remove the stats lock in the process.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

At the moment we try and replenish the receive ring on every rx interrupt.
We even have a pool->threshold but aren't using it.

To limit the maximum latency incurred when refilling, change the threshold
from 1/2 to 7/8 and reduce the largest rx pool from 768 buffers to 512 which
should be more than enough.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace some modulus operators with an increment and compare to avoid
an integer divide.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This fixes the following opps which can occur when trying to deallocate
receive buffer pools when changing the MTU of an active ibmveth device.

Oops: Kernel access of bad area, sig: 11 [#1]
NIP: d000000004db00e8 LR: d000000004db00ac CTR: 0000000000591038
REGS: c00000007fff39d0 TRAP: 0300   Not tainted  (2.6.36-rc1)
MSR: 8000000000009032 <EE,ME,IR,DR>  CR: 22248244  XER: 00000002
DAR: 0000000000000488, DSISR: 0000000042000000
TASK = c00000007c463790[6531] 'netserver' THREAD: c00000007a154000 CPU: 0
GPR00: 0000000000000000 c00000007fff3c50 d000000004dbd360 0000000000000001
GPR04: 0000000000000001 1fffffffffffffff 000000000000043c c00000007a8e9f60
GPR08: c00000007a8e9e20 0000000000000245 0000000000000488 0000000000000000
GPR12: 00000000000000c0 c000000006d70000 c00000007bfec098 c00000007bfebc2c
GPR16: c00000007a157c78 0000000000000000 0000000000000001 0000000000000000
GPR20: 0000000000000001 0000000000000010 c000000000b51180 c00000007a8e9d90
GPR24: c00000007a8e9da0 c00000007a8e9580 00000000000005ea 00000000000002ff
GPR28: 0000000000000004 0000000000000080 c000000000a946f8 c00000007a8e9d80
NIP [d000000004db00e8] .ibmveth_remove_buffer_from_pool+0xe8/0x130 [ibmveth]
LR [d000000004db00ac] .ibmveth_remove_buffer_from_pool+0xac/0x130 [ibmveth]
Call Trace:
[c00000007fff3c50] [d000000004db00ac] .ibmveth_remove_buffer_from_pool+0xac/0x130 [ibmveth] (unreliable)
[c00000007fff3cf0] [d000000004db31dc] .ibmveth_poll+0x30c/0x460 [ibmveth]
[c00000007fff3dd0] [c00000000042c4b8] .net_rx_action+0x178/0x278
[c00000007fff3eb0] [c000000000093cf0] .__do_softirq+0x118/0x1f8
[c00000007fff3f90] [c00000000002ab3c] .call_do_softirq+0x14/0x24
[c00000007a157600] [c00000000000e3e4] .do_softirq+0xec/0x110
[c00000007a1576a0] [c000000000093394] .local_bh_enable_ip+0xb4/0xe0
[c00000007a157720] [c0000000004f0bac] ._raw_spin_unlock_bh+0x3c/0x50
[c00000007a157790] [c0000000004186e0] .release_sock+0x158/0x188
[c00000007a157840] [c000000000479660] .tcp_recvmsg+0x560/0x9b8
[c00000007a157970] [c0000000004a0d78] .inet_recvmsg+0x80/0xd8
[c00000007a157a00] [c000000000413e28] .sock_recvmsg+0x128/0x178
[c00000007a157bf0] [c0000000004164ac] .SyS_recvfrom+0xb4/0x148
[c00000007a157d70] [c000000000411f3c] .SyS_socketcall+0x274/0x360
[c00000007a157e30] [c0000000000085b4] syscall_exit+0x0/0x40
Reported-by: NRafael Camarda Silva Folco <rfolco@linux.vnet.ibm.com>
Signed-off-by: NRobert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The order of freeing the IRQ and freeing the device in firmware
in ibmveth_close can cause the adapter to become unusable after a
subsequent ibmveth_open.  Only a reboot of the OS will make the
network device usable again. This is seen when cycling the adapter
up and down while there is network activity.

There is a window where an IRQ will be left unserviced (H_EOI will not
be called).  The solution is to make a VIO_IRQ_DISABLE h_call, free the
device with firmware, and then call free_irq.
Signed-off-by: NRobert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use kcalloc or kzalloc rather than the combination of kmalloc and memset.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,y,flags;
statement S;
type T;
@@

x =
-   kmalloc
+   kcalloc
           (
-           y * sizeof(T),
+           y, sizeof(T),
                flags);
 if (x == NULL) S
-memset(x, 0, y * sizeof(T));

@@
expression x,size,flags;
statement S;
@@

-x = kmalloc(size,flags);
+x = kzalloc(size,flags);
 if (x == NULL) S
-memset(x, 0, size);
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adds support for resuming from suspend for IBM virtual ethernet devices.
We may have lost an interrupt over the suspend, so we just kick the
interrupt handler to process anything that is outstanding.
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes from drivers/net/ all the unnecessary
return; statements that precede the last closing brace of
void functions.

It does not remove the returns that are immediately
preceded by a label as gcc doesn't like that.

It also does not remove null void functions with return.

Done via:
$ grep -rP --include=*.[ch] -l "return;\n}" net/ | \
  xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }'

with some cleanups by hand.

Compile tested x86 allmodconfig only.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that core network takes care of trans_start updates, dont do it
in drivers themselves, if possible. Drivers can avoid one cache miss
(on dev->trans_start) in their start_xmit() handler.

Exceptions are NETIF_F_LLTX drivers
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Converts the list and the core manipulating with it to be the same as uc_list.

+uses two functions for adding/removing mc address (normal and "global"
 variant) instead of a function parameter.
+removes dev_mcast.c completely.
+exposes netdev_hw_addr_list_* macros along with __hw_addr_* functions for
 manipulation with lists on a sandbox (used in bonding and 80211 drivers)
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Constify struct sysfs_ops.

This is part of the ops structure constification
effort started by Arjan van de Ven et al.

Benefits of this constification:

 * prevents modification of data that is shared
   (referenced) by many other structure instances
   at runtime

 * detects/prevents accidental (but not intentional)
   modification attempts on archs that enforce
   read-only kernel data at runtime

 * potentially better optimized code as the compiler
   can assume that the const data cannot be changed

 * the compiler/linker move const data into .rodata
   and therefore exclude them from false sharing
Signed-off-by: NEmese Revfy <re.emese@gmail.com>
Acked-by: NDavid Teigland <teigland@redhat.com>
Acked-by: NMatt Domsch <Matt_Domsch@dell.com>
Acked-by: NMaciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: NHans J. Koch <hjk@linutronix.de>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Acked-by: NJens Axboe <jens.axboe@oracle.com>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch replaces dev->mc_count in all drivers (hopefully I didn't miss
anything). Used spatch and did small tweaks and conding style changes when
it was suitable.

Jirka
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Not as fancy as coccinelle.  Checkpatch errors ignored.
Compile tested allyesconfig x86, not all files compiled.

grep -rPl --include=*.[ch] "\brequest_irq\s*\([^,\)]+,\s*\&" drivers/net | while read file ; do \
	perl -i -e 'local $/; while (<>) { s@(\brequest_irq\s*\([^,\)]+,\s*)\&@\1@g ; print ; }' $file ;\
done
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In a couple of cases collapse some extra code like:
   int retval = NETDEV_TX_OK;
   ...
   return retval;
into
   return NETDEV_TX_OK;
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.

Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

netdev->dev_addr changed from being an array to being a pointer, so we
should not take its address for memcpy().
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Patch fixes issues with dev->dev_addr changing from array to pointer.
Hopefully there are no others.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the near future, the driver core is going to not allow direct access
to the driver_data pointer in struct device.  Instead, the functions
dev_get_drvdata() and dev_set_drvdata() should be used.  These functions
have been around since the beginning, so are backwards compatible with
all older kernel versions.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Following the removal of the unused struct net_device * parameter from
the NAPI functions named *netif_rx_* in commit 908a7a16, they are
exactly equivalent to the corresponding *napi_* functions and are
therefore redundant.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These are powerpc specific drivers.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

These variables are only used with an interface that just dumps their
values into registers to be passed to the hypervisor. The arguments
to that interface are declared to be "unsigned long", so make these
variables match.  The macros are only used with these variables, so make
them match as well.

This code is currently only built for 64bit powerpc, so the transformation
is really a noop.  If the interface was ever ported to 32 bit, it would
almost certainly still use registers to pass the parameters and so
"unsigned long" would still be appropriate.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 908a7a16 ("net: Remove unused
netdev arg from some NAPI interfaces") missed two spots.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When the napi api was changed to separate its 1:1 binding to the net_device
struct, the netif_rx_[prep|schedule|complete] api failed to remove the now
vestigual net_device structure parameter.  This patch cleans up that api by
properly removing it..
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have some reasons to kill netdev->priv:
1. netdev->priv is equal to netdev_priv().
2. netdev_priv() wraps the calculation of netdev->priv's offset, obviously
   netdev_priv() is more flexible than netdev->priv.
But we cann't kill netdev->priv, because so many drivers reference to it
directly.

This patch is a safe convert for netdev->priv to netdev_priv(netdev).
Since all of the netdev->priv is only for read.
But it is too big to be sent in one mail.
I split it to 4 parts and make every part smaller than 100,000 bytes,
which is max size allowed by vger.
Signed-off-by: NWang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The generic packet receive code takes care of setting
netdev->last_rx when necessary, for the sake of the
bonding ARP monitor.

Drivers need not do it any more.

Some cases had to be skipped over because the drivers
were making use of the ->last_rx value themselves.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This converts pretty much everything to print_mac. There were
a few things that had conflicts which I have just dropped for
now, no harm done.

I've built an allyesconfig with this and looked at the files
that weren't built very carefully, but it's a huge patch.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a ibmveth bug where bad UDP checksums are being transmitted
when checksum offloading is enabled.
The hypervisor does checksum offloading only on TCP packets, so ibmveth calls
skb_checksum_help() for any other protocol.  The bug happens because
the packet is being modified after the DMA map, so we would need a memory
barrier before making the hypervisor call.  Reordering the code so that the
DMA map happens after skb_checksum_help() has the additional advantage of
fixing a DMA map leak if skb_checksum_help() where to fail.
Signed-off-by: NSantiago Leon <santil@us.ibm.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

The addition of an argument to dma_mapping_error() in commit
8d8bb39b "dma-mapping: add the device
argument to dma_mapping_error()" left a bit of fallout:

drivers/net/ibmveth.c:263: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:264: error: expected ')' before 'goto'
drivers/net/ibmveth.c:284: error: expected expression before '}' token
drivers/net/ibmveth.c:297: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:298: error: expected ')' before 'dma_unmap_single'
drivers/net/ibmveth.c:306: error: expected expression before '}' token
drivers/net/ibmveth.c:491: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:927: error: too few arguments to function 'dma_mapping_error'
drivers/net/ibmveth.c:927: error: expected ')' before '{' token
drivers/net/ibmveth.c:974: error: expected expression before '}' token
drivers/net/ibmveth.c:914: error: label 'out' used but not defined m
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER
architecture does:

This enables us to cleanly fix the Calgary IOMMU issue that some devices
are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423).

I think that per-device dma_mapping_ops support would be also helpful for
KVM people to support PCI passthrough but Andi thinks that this makes it
difficult to support the PCI passthrough (see the above thread).  So I
CC'ed this to KVM camp.  Comments are appreciated.

A pointer to dma_mapping_ops to struct dev_archdata is added.  If the
pointer is non NULL, DMA operations in asm/dma-mapping.h use it.  If it's
NULL, the system-wide dma_ops pointer is used as before.

If it's useful for KVM people, I plan to implement a mechanism to register
a hook called when a new pci (or dma capable) device is created (it works
with hot plugging).  It enables IOMMUs to set up an appropriate
dma_mapping_ops per device.

The major obstacle is that dma_mapping_error doesn't take a pointer to the
device unlike other DMA operations.  So x86 can't have dma_mapping_ops per
device.  Note all the POWER IOMMUs use the same dma_mapping_error function
so this is not a problem for POWER but x86 IOMMUs use different
dma_mapping_error functions.

The first patch adds the device argument to dma_mapping_error.  The patch
is trivial but large since it touches lots of drivers and dma-mapping.h in
all the architecture.

This patch:

dma_mapping_error() doesn't take a pointer to the device unlike other DMA
operations.  So we can't have dma_mapping_ops per device.

Note that POWER already has dma_mapping_ops per device but all the POWER
IOMMUs use the same dma_mapping_error function.  x86 IOMMUs use device
argument.

[akpm@linux-foundation.org: fix sge]
[akpm@linux-foundation.org: fix svc_rdma]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix bnx2x]
[akpm@linux-foundation.org: fix s2io]
[akpm@linux-foundation.org: fix pasemi_mac]
[akpm@linux-foundation.org: fix sdhci]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix sparc]
[akpm@linux-foundation.org: fix ibmvscsi]
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Enable ibmveth for Cooperative Memory Overcommitment (CMO).  For this driver
it means calculating a desired amount of IO memory based on the current MTU
and updating this value with the bus when MTU changes occur.  Because DMA
mappings can fail, we have added a bounce buffer for temporary cases where
the driver can not map IO memory for the buffer pool.

The following changes are made to enable the driver for CMO:
 * DMA mapping errors will not result in error messages if entitlement has
   been exceeded and resources were not available.
 * DMA mapping errors are handled gracefully, ibmveth_replenish_buffer_pool()
   is corrected to check the return from dma_map_single and fail gracefully.
 * The driver will have a get_desired_dma function defined to function
   in a CMO environment.
 * When the MTU is changed, the driver will update the device IO entitlement
Signed-off-by: NRobert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: NBrian King <brking@linux.vnet.ibm.com>
Signed-off-by: NSantiago Leon <santil@us.ibm.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>